The objective of this research project is to document the role of implicit sequence learning in understanding and explaining the enormous variability in outcome and benefit in deaf children following cochlear implantation. The first aim of this project is to determine the extent to which deaf children with cochlear implants (CIs) have a disturbance in implicit visual sequence learning abilities compared to normal-hearing (NH) children. The working hypothesis is that some deaf children with CIs have a disturbance in implicit learning of complex visual sequential patterns and it is this learning disturbance that can partly explain why many children with CIs show language delays. To test this hypothesis, we will investigate two types of implicit sequence learning abilities (fixed and probabilistic pattern learning) in a group of 30 5-9 year-old deaf children with CIs and an age-matched NH group. The second aim of this project is to assess the association between implicit sequence learning and spoken language processing abilities. We propose to assess the hypothesis that individual differences in the ability to implicitly learn complex visual sequential patterns will be significantly correlated with several different measures of spoken language processing. To test this hypothesis, we will assess the same two groups of children on a number of conventional tests of language processing and outcome (i.e., PPVT, PBK, LNT, VABS, and lexically-controlled sentences), at the same time that sequence learning is measured as well as 12-18 months later. At the conclusion of this project, we expect to demonstrate that deaf children with CIs on average have a disturbance in non-auditory implicit sequence learning abilities, for both fixed and more complex probabilistic visual sequential patterns. We also expect to demonstrate a significant and strong association between implicit visual sequence learning abilities and language outcomes as measured both at the time of testing and 12-18 months later, in both NH children and deaf children with CIs. This work is both clinically and theoretically significant because it will for the first time show that deaf children with CIs are impaired on fundamental cognitive learning abilities that are in turn associated with spoken language processing measures. Our findings will provide support for the hypothesis that implicit sequence learning abilities make a strong contribution to language outcomes in both NH children and deaf children with CIs. The results of this project will provide the foundation for new theoretical perspectives regarding the consequences of auditory deprivation on basic cognitive learning abilities and suggest several new avenues of habilitation for children who are doing poorly with their cochlear implants. We expect the findings from this research project to demonstrate that basic and fundamental cognitive learning abilities make a strong contribution to language outcomes in deaf children with cochlear implants. This knowledge will provide the theoretical and empirical foundation for improved prediction of and treatment for the deaf children who may be doing poorly with their implants.